Nasal assembly

ABSTRACT

A vent assembly includes at least one vent having a first end configured to face atmosphere and a second end opposite the first end, and a central portion provided between the first and second ends including a substantially cylindrical cross-sectional shape, wherein the second end includes a counter bore.

CROSS-REFERENCE TO APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.12/926,213, filed Nov. 2, 2010, now U.S. Pat. No. 8,757,162, which is acontinuation of U.S. patent application Ser. No. 11/101,657, filed Apr.8, 2005, now U.S. Pat. No. 7,942,150, which claims the benefit of U.S.Provisional Application Nos. 60/560,610, filed Apr. 9, 2004, and60/632,193, filed Dec. 2, 2004, each of which is incorporated herein byreference in its entirety.

FIELD OF THE INVENTION

The present invention relates to a nasal assembly used for treatment,e.g., of Sleep Disordered Breathing (SDB) with Continuous PositiveAirway Pressure (CPAP) or Non-invasive Positive Pressure Ventilation(NPPV).

BACKGROUND OF THE INVENTION

Some nasal assemblies used in the treatment of SDB are designed forinsertion into the nasal passages of the patient. Air or otherbreathable gas is supplied by a blower and passed along a flexibleconduit to the nasal assembly.

The nasal assembly generally includes a relatively rigid shell, e.g., aframe, and a pair of nozzles (which may be in the form of nasal pillows,nasal prongs, cannula, or nasal puffs) that are mounted on the rigidshell and structured to be inserted into the nasal passages of thepatient. The nozzles are usually held in place using a headgearassembly, the relatively rigid shell and headgear assembly being joinedusing some form of connector.

One form of known nasal assembly is described in U.S. Pat. No. 4,782,832(Trimble et al.). Trimble discloses a nasal puff assembly 20 thatincludes a nasal puff 22 adapted to be worn adjacent the nose of apatient, together with a harness assembly 24 adapted to be worn over thehead of the patient. The harness assembly 24 is designed to operativelyhold puff 22 adjacent and partially within the nasal passages of thepatient.

The puff 22 is in the form of a generally Y-shaped rigid hollow plenumchamber 28 together with a pair of laterally spaced apart nares elements30. Adjustability of the nares elements 30 may be provided by rotatablymounting the elements 30 to the plenum chamber 28 and mounting theelements 30 in slots permitting selective lateral positioning of theelements 30 with respect to each other. Also, the harness assembly 24may be adjusted to adjust the fit and seal of the nares elements 30during use. That is, the force required to maintain a sufficient seal isdirectly associated with the force required to maintain a desired fit.Thus, adjustment of the fit or stability of the nasal assembly directlyaffects the seal, which can adversely affect patient comfort.

Other examples of nasal pillows or cannula mounted to rigid shells aredisclosed in U.S. Pat. Nos. 5,724,965 and 6,431,172.

A nasal mask assembly manufactured by Viasys, i.e., Spiritus, includes aplenum chamber with a pair of adjacent or laterally spaced nareselements. A harness assembly is engaged with the plenum chamber toadjust the fit and seal of the nares elements during use. Similar toTrimble, adjustment of the fit or stability of the nasal assemblydirectly affects the seal, which can adversely affect patient comfort.

A nasal mask assembly manufactured by InnoMed, i.e., Nasal Aire,includes a plenum chamber with a pair of adjacent or laterally spacednares elements. The nares elements are structured to engage within themucosal surfaces or internal passages of the patient's nose to maintainthe nasal mask assembly on the patient's face and to provide a seal.See, e.g., U.S. Pat. No. 5,533,506.

A nasal mask assembly manufactured by Stevenson Industries (see U.S.Pat. No. 6,012,455), i.e., CPAP-Pro, includes a dental anchor, aplatform, and air supply tubes having nasal pads, wherein the platformsupports the air supply tubes. The dental anchor is sized to be engagedbetween the teeth in the patient's mouth so as to retain the assembly inplace.

PCT Application Publication No. WO 00/13751 discloses a device thatincludes gas delivery elements positioned into engagement with thepatient's nose by a mouthpiece fitted to the patient's teeth.

A common problem with known nasal assemblies, such as those discussedabove, is patient comfort. For example, the prongs tend to irritate thepatient's nose due to the tension applied by the headgear assembly thatpulls the rigid shell and prongs towards the patient's nose.

Another problem is achievement of a sealing fit with the patient's nasalpassages without sacrificing patient comfort.

Another problem is irritation of the inside of the patient's nostrilscaused by contact with the prongs, e.g., an edge thereof.

Another problem is irritation of the inside of the patient's nostrilscaused by air jetting (air flow irritation) from the prongs.

Another problem is adjustment of the nasal assemblies relative to thenose and/or head of the patient so as to accommodate various shapes andangles of patient's noses.

Still another problem is the direct association between sealing andstability forces that can affect patient comfort.

SUMMARY OF THE INVENTION

One aspect of the invention is directed towards a nasal assembly thatprovides more comfort to the patient.

Another aspect of the invention is directed towards a nasal assemblythat provides an effective seal with the patient's nasal passages.Preferably, the nasal assembly is a nozzle assembly including nozzleswhich comfortably come into contact with the external rim of the naresand avoid the sensitive internal passages (e.g., mucosal surfaces orinternal passages) of the nasal passage.

Still another aspect of the invention is directed towards a nasalassembly that does not rely on tension from the headgear assembly toprovide an effective seal between the nozzles and the patient's nasalpassages.

Still another aspect of the invention is directed towards a nasalassembly that is unobtrusive.

Still another aspect of the invention is directed towards a nasalassembly that is easy to use.

Still another aspect of the invention is directed towards a nasalassembly that maintains a headgear adjustment setting.

Another aspect is to provide a vent having a profile that is configuredto provide improved performance.

Still another aspect of the invention is directed towards a nasalassembly that helps decouple sealing and stability forces. Specifically,one aspect of the invention is directed towards a nasal assembly that isstructured such that the stability forces that act to maintain the nasalassembly on the patient's face are separated or at least betterdistinguished from the sealing forces that act to maintain a sealbetween the nasal assembly and the patient's face.

Yet another aspect of the invention is directed towards a nasal assemblythat provides a greater range of movement for nozzles of the nasalassembly.

Another aspect of the invention provides a nasal assembly for deliveringbreathable gas to a patient. The nasal assembly includes a frame havinga main body and a side frame member provided on each lateral side of themain body, each side frame member including an integrally formed firstconnector portion. A nozzle assembly includes a gusset or base portionand a pair of nozzles. The nozzle assembly is coupled with the main bodyof the frame with the pair of nozzles structured to sealingly engagewith nasal passages of a patient's nose in use. A pair of inlet conduitsare structured to deliver breathable gas into the frame and nozzleassembly for breathing by the patient. A pair of second connectorportions are removably and rotatably connected to respective firstconnector portions of the frame. The second connector portions are incommunication with the inlet conduits via angle connectors. A headgearassembly is removably connected to at least one of the second connectorportions and the angle connectors so as to maintain the frame and thenozzle assembly in a desired adjusted position on the patient's face.

In accordance with yet another aspect, a nasal assembly for deliveringbreathable gas to a patient comprises a frame having a main body and aside frame member provided on each lateral side of the main body; apatient interface provided to the main body of the frame; an elbowstructured to deliver breathable gas into the frame and patientinterface for breathing by the patient, the elbow being structured to beremovably connected to each lateral side of the frame; and a plugstructured to be removably connected to each lateral side of the frame.The positions of the plug and elbow may be selectively interchanged.

Still another aspect is to provide a nasal assembly including a baffleprovided to the frame.

Yet another aspect of the invention is to provide a nasal assemblyincluding a vent provided to the frame that allows for the exit ofexhaled gas.

Other aspects, features and advantages of this invention will becomeapparent from the following detailed description when taken inconjunction with the accompanying drawings, which are a part of thisdisclosure and which illustrate, by way of example, principles of thisinvention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings facilitate an understanding of the variousembodiments of this invention. In such drawings:

FIG. 1 is a perspective view of yet another embodiment of a nasalassembly;

FIG. 2 is an isometric view illustrating a portion of the nasal assemblyshown in FIG. 1;

FIG. 3 is a cross-sectional view of a portion of a nasal assemblyaccording to the present invention;

FIGS. 4 and 5 illustrate cross-sectional views of a vent apertureaccording to the present invention;

FIG. 6 is a partial enlarged cross-sectional view of the left hand sideof FIG. 3;

FIG. 7 is an partial enlarged cross-sectional view of the right handside of FIG. 3;

FIG. 8 is an exploded perspective view showing the interface betweenseal ring and elbow swivel according to an embodiment of the presentinvention;

FIG. 9 is a partial cross-sectional view of a portion of the maskassembly shown in FIG. 1;

FIG. 10 illustrates still another embodiment of the present inventionwith an integral plug and seal assembly;

FIGS. 11 and 12 illustrate a tube retainer according to an embodiment ofthe present invention;

FIG. 13 illustrates another tube retainer according to an embodiment ofthe present invention;

FIGS. 14-18 illustrate another tube retainer according to an embodimentof the present invention;

FIGS. 19-31 illustrate yet another embodiment of the present invention;

FIGS. 32-35 illustrate still another embodiment of the presentinvention;

FIGS. 36-41 illustrate a plug in accordance with an embodiment of thepresent invention;

FIG. 42 illustrates a vent in accordance with an embodiment of thepresent invention;

FIGS. 43-45A and 45C-45H illustrate vents in accordance with furtherembodiments of the present invention;

FIG. 45B illustrates a prior art vent;

FIGS. 46-48 illustrate baffles in accordance with embodiments of theinvention;

FIGS. 49-51 illustrate yet another swivel elbow according to anembodiment of the invention;

FIGS. 52-54 illustrate a frame according to an embodiment of theinvention; and

FIGS. 55-58 illustrate further alternative embodiments of the presentinvention.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS

The following includes descriptions of several illustrated embodimentsof the present invention. Each illustrated embodiment includes featuresthat may be used with and/or in the other embodiments, or with theembodiments and/or components described in U.S. Non-Provisionalapplication Ser. No. 10/781,929, as would be apparent to those ofordinary skill in the art.

FIGS. 1-13 illustrate another preferred embodiment of the presentinvention. As shown in FIG. 1, a mask assembly 600 includes headgear 602and a cushion assembly 604 (also referred to as a nozzle assembly).Headgear 602 is designed to capture the crown of the patient's head.Adjustment of strap tension can be accomplished by pulling loose tabs603 on the top of the head in opposite directions. The pulling directionis not aligned with the force the nozzle assembly applies to thepatient. Therefore, the patient is more isolated from the strapadjustment forces. Yokes provide stability to the sides. Yokes 608retain at least a partial portion of the basic shape of headgear, whichfacilitates donning of the headgear. Headgear need not includeadjustability toward front of the face, as all adjustment of headgearcan be effected at the back or top of the head.

In the embodiment of FIG. 1, one end of the cushion assembly 604 isprovided with a plug 622 and the other end is provided with a swivelelbow 612. The positions of the swivel elbow 612 and the plug 622 may beinterchanged, according to preference, e.g., the typical sleepingposition of the patient. An air delivery tube 606 is joined to theswivel elbow 612. The air delivery tube 606 may include a swivelconnector 607 and includes an end 615 which also may be provided with aswivel connector. The end 615 is provided with a source of pressurizedgas.

As shown in FIG. 1, the elbow 612 is angled about 120° from the cushionassembly 604. This helps to keep the tube out of line of sight, tominimize pressure drop and to maintain the flexion point of tube asclose to the face as possible. However, the elbow may have a typical 90°bend as shown, e.g., in FIGS. 2 and 3.

FIG. 2 is a schematic perspective view of the mask assembly 600 shown inFIG. 1, but only yokes 608 of headgear 602 are shown, without thestraps, e.g., 904, etc. The yoke 608 may include a yoke ring 610. Asshown in FIG. 2, the cushion assembly may be adjustably rotated withrespect to headgear, to a position which best fits the patient. In FIG.2, the ring 610 of the yoke 608 of the headgear includes an alignmentmarker 611 a and the cushion includes a plurality of alignment markers611 b that can be selectively aligned with marker 611 a.

FIG. 3 is a cross-sectional view of a portion of the cushion assembly604. In particular, the cushion assembly 604 includes a frame 616 whichsupports a cushion 617. The frame 616 includes a first connector portion618 provided to each end of the frame 616 and/or cushion 617. Each firstconnector portion 618 is provided with or to a seal ring 614. Both sealring and plug are examples of second connector portions that areconnected or otherwise provided to the first connector portions 618. Asseen in FIG. 3, the left hand side of the mask assembly includes theplug 622 while the right hand side of the mask assembly includes theswivel elbow 612, i.e., the reverse arrangement view shown in FIGS. 1and 2.

FIG. 3 shows that the cushion 617 includes a plurality of vent apertures619, each of which is designed to reduce noise. Cross-sections of twopossible aperture profiles are shown in FIGS. 4 and 5. In FIG. 5, theend 617 a displaces any potential noise creating flash (i.e., a moldingseam) out of main air path through bore of vent. Stated differently, themolding seam is moved from a position from where it could potentiallycreate noise, to a position where it is less likely to create noise.

FIG. 6 is a partial cross-sectional view showing the interaction betweenthe seal ring 614, first connector portion 618 and the plug 622. Inparticular, the seal ring 614 may be provided with first and secondprotrusions 624, 626, respectively. The first protrusion 624 mayinteract with a groove 618 a provided in the first connector portion618, for sealing and/or locking purposes. The second protrusion 626 mayinteract with a groove 628 provided in the plug 622, the sealing and/orlocking purposes. As shown in FIG. 6, each seal ring 614 includes agroove 630 to receive a respective one of the rings 610 of the yoke 608.In FIG. 6, the yoke 608 is not shown.

FIG. 7 is an enlarged partial cross-sectional view of the mask assembly600 on the right hand side of FIG. 3. A first end 612 a of the swivelelbow 612 is inserted in and received within the first connector portion618. The first end 612 a may include an enlarged head portion whichprevents inadvertent dislodgement of the swivel elbow 612 from theassembly. The front end 612 a may include at least one slot 613 to allowthe enlarged head portion to reduce its diameter upon insertion byresiliently flexing. Preferably, there are a plurality of such slots,e.g., four slots. The seal ring 614 may include first and secondprotrusions 624, 626, as described above. In this case, the secondprotrusion 626 may interact by friction with the outer circumference ofthe swivel elbow 612, and provide a seal. Moreover, the swivel elbow 612may be provided with a groove or other structure to receive the secondprotrusion 626.

FIG. 7 also schematically shows that the swivel elbow 612 and the sealring 614 may include a swivel stop 631. For example, the swivel stop 631may be formed as part of the yoke 608.

Alternatively or in addition, as shown in FIG. 8, the swivel elbow 612may be provided with a ring 633 including a protrusion 634. The sealring 614 may be modified to include swivel stops 632. Accordingly, theprotrusion 634 may rotate along with swivel elbow 612 until theprotrusion 634 abuts against the swivel stop 632. Therefore, movement ofthe air delivery tube 606 can be confined with a predetermined range ofmovement, e.g., about 220°-300°, and preferably 250°-270°, thusminimizing or avoiding undesirable contact between the air delivery tubeand the patient.

FIG. 9 is a partial cross-sectional view of the assembly of the frame,first connector portion 618, yoke 608, seal ring 614 and plug 622. FIG.9 shows the plug 622 to be inserted in the right hand side of thecushion assembly 604, as shown in FIG. 1.

FIG. 10 shows an alternative embodiment of the invention in which theplug and seal ring are formed of a single integral piece. As shown inFIG. 10, the seal ring 636 includes a flange portion 638 which generallyfollows along a contour of the yoke 608. This is best shown in thecross-sectional view of FIG. 3 where the seal ring 614 and the yoke 608are positioned closely adjacent one another.

These and other illustrated embodiments may provide for improveddecoupling of the air delivery tube 606 and/or swivel elbow 612 from thecushion assembly 604. In addition, these and other embodiments provide achoice of tube routing, which can be either up or down or on the left orright hand sides of the cushion assembly 604. As such, these embodimentsmay be perceived as less obtrusive and is significantly lighter, andincluding relatively few parts, which facilitates manufacture, assemblyand cleaning.

The swivel elbow 612 may be provided with a quick release mechanism (notshown). The swivel elbow 612, as shown in FIG. 7, is able to fit andsnap into the mask frame 616. This construction allows free swivelingwithin the frame 616, between a range of defined angles, therebyensuring that the tube does not get into an uncomfortable position withrespect to the head and pillow.

The seal ring 614 is structured such that it cooperates with thegeometry of the elbow swivel 612. In addition, the seal ring 614 may beconnected to the ring 610 of the yoke 608. The seal ring 614 may bepermanently connected to the ring 610, e.g., via co-molding. Forexample, the swivel stop 631 in FIG. 7 may be formed as part of the ring610. The first connector portion 618 on each side of the frame 616 maybe rotated with respect to the seal ring 614, to thereby position thecushion assembly 604 accordingly. The seal ring 614 seals the swivelelbow 612 preferably with minimum friction. Each seal ring 614 mayaccommodate either the plug 622 or the swivel elbow 612. The seal ring614 is large enough for patients to handle, especially patients withreduced manual dexterity.

The plug 622 may be press fit into the seal ring 614. The plug 622 canalso be designed to be press fit into the frame. The plug 622 may bemade from hard polymer, for example, polypropylene. A recess (not shown)may be provided to remove the plug 622. The plug functions to seal theframe and cushion assembly on the side opposing the air delivery tube.The plug 622 is large enough for patients to handle, even with reducedmanual dexterity.

The tubing 606 may be permanently attached to the end of the swivelelbow 612. However, a push-on friction connection may also be suitable.The tube length may be between 200 mm and 400 mm, preferably 250 and 350mm, for example, or any other length which will not interfere with thepatient's face.

As shown in FIGS. 7 and 8, respectively, the yokes 608 and seal ring 614may be provided with structure to limit the angular or rotationalmovement of the swivel elbow 612 with respect to the first connectorportion 618.

Further, the headgear and/or yoke may be provided with a tube retentionfeature to control the tube position. For example, simple VELCRO® strapsmay be provided along some portion of the headgear to restrain movementof the air delivery tube.

In the example shown in FIGS. 11 and 12, a tube retainer 900 includes afirst portion 902 to be connected or attached to one of the straps ofheadgear. For example, the first portion 902 can be in the form of aloop that is attached to a portion 904 of headgear strap shown inFIG. 1. Attachment can be accomplished by threading the headgear strap904 though the first portion 902 before the headgear strap 904 isthreaded through the headgear buckle 906. The retainer 900 includes asecond portion 908 provided or attached to the first portion 902. Thesecond portion 908 may be made of a resilient plastic that retains theshape shown in FIG. 11, with a gap 910 defined between two ends 912 ofthe second portion 908. The gap 910 is sized to be smaller than thediameter of the air delivery tube 606, so as to reliably hold the tube606. Alternatively, the second portion 908 can be a VELCRO® loop, withthe ends 912 including the mating hooks and loops. As shown in FIGS. 11and 12, the second portion may include one or more slots 914 to receiveribs 916 (FIG. 1) of the air delivery tube 606, to thereby prevent axialsliding of the tube 606. With this arrangement, the tube 606 can bereliably held in a position over the patient's head.

FIG. 13 illustrates a plan view of a tube retainer, wherein likereference numbers relate to like parts. In FIG. 13, exemplary dimensionsof the tube retainer are shown. It is to be noted that these dimensionsare examples only, and the dimensions can be changed up to about ±20% ofthe values shown therein. In the embodiment of FIGS. 11-13, firstportion 902 is optional as second portion 908 alone can affix the tubeto the headgear.

FIGS. 14-18 illustrate a retainer 10 according to yet another embodimentof the present invention. The retainer 10, as shown in FIG. 14, includesa main body 12 and a tab 14. The tab 14 includes hook-type fasteners onsurface 16 while main body includes loop-type fasteners on surface 18,as shown in FIG. 15.

FIGS. 16-18 illustrate the positioning of the retainer 10 on a samplepatient's head. As seen in FIGS. 16-18, the retainer 10 is provided toguide the air delivery tube 606 around the patient's head. The retainer10 engages a portion of head strap 904 and is then wrapped around airdelivery tube 606 with the hook and loop fasteners on surfaces 16 and 18engaged.

Main body 12 of retainer 12 can be formed of any suitable material, suchas a Breath-O-prene™. The Breath-O-prene™ may be provided with anunderside fabric layer if desired for added comfort. All materials usedin constructing retainer 10 are available from Accumed Technologies,Inc.

The nasal assemblies described above and below have several advantages.For example, the nasal assemblies are unobtrusive due to their smalloverall size and weight. The nasal assemblies provide a high level ofcomfort due to the minimal force applied to the patient's nose—andcontact with the bridge can be eliminated. The nasal assemblies are easyto use and include minimal parts and adjustments, e.g., the inletconduits can be easily adjusted to extend upwardly over the head of thepatient or downwardly below the chin of the patient. The pressurizedsupply can be easily connected to and disconnected from the connectorswithout altering the headgear setting. Also, the nasal assemblies allowfor greater nozzle range of motion to accommodate a wide range ofpatients. That is, the nozzles can be rotated with respect to thepatient's face by rotating the frame relative to the headgear assembly.Further, strap tension need not be as high as the area of contact withthe face is less. The headgear provides stability, e.g., the yokes helpmaintain the mask assembly's position on the face. The adjustment of theheadgear is designed such that the force required to tighten the strapsis not applied to the patient's face, e.g., the straps can be pulled inopposite directions above the head to counteract one another. It isrelatively easy to find balance between performance and comfort. Inaddition, the weight, noise level, and/or number of parts of the maskassembly is reduced.

An Appendix including additional drawings and depictions of variousaspects of preferred embodiments of the invention is included in U.S.Provisional Application No. 60/529,696, filed Dec. 16, 2003 andincorporated herein by reference in its entirety. To the extent that anydrawing in the labeled Figures or the Appendix includes dimensions,those dimensions are exemplary only and may be changed without departingfrom the scope of the disclosure.

FIG. 19 illustrates a partial exploded view of another embodiment of thepresent invention. Yoke 608 includes a widened portion 608 a intended toengage with a corresponding widened portion 630 a adjacent or formed aspart of groove 630. In addition, yoke 608 includes a recess 608 bintended to receive ear 638 of seal ring 614. In a further embodiment,yoke 608 and seal ring 614 may be formed in one piece. Also, the yokeand headgear could be formed of one piece, instead of using stitching orother fasteners. As can be seen in FIG. 20, the yoke 608 and seal ring614 can be snap fit relative to one another, e.g., via shoulder 621. Bythis structure, the yoke and ring are prevented from rotating relativeto one another. FIG. 20 also shows the general position of yoke flexpoint P, which allows a good fit with the patient.

FIGS. 21 to 31 illustrate further views of the embodiment shown in FIGS.19 and 20. Another aspect of the arrangement is that the ring 610 of theyoke 608 is angularly offset with respect to the main body 609 of theyoke 608. Compare FIG. 21 with FIG. 3, e.g., where the main body 609 inFIG. 21 is twisted. For example, front side 609 a in FIG. 21 ispositioned laterally outward in comparison to rear side 609 b in FIG.21. This structure helps to bias the bottom portion of the yoke 608towards the patient's face, so that the yoke more closely follows thecontours of the patient's face.

FIGS. 32-35 illustrate a further embodiment of the present invention.This embodiment is similar to that shown and described in FIGS. 19-31.However, there are two main differences. First, the elbow 612 is free torotate 360° within seal ring 614. As shown in the partial exploded viewof FIG. 33, seal ring 614 does not include stops 632 and elbow 612 doesnot include protrusion 634, as compared to what is shown in FIG. 19.

Second, as shown in FIG. 34, seal ring 614 includes a selectivelyremovable and insertable cap 614A. In other words, the plug 622 in FIG.9 is made in two parts rather than one. The cap 614A may also include orbe a vent, instead of or supplemental to the vent provided on thecushion. For example, at least a portion of the outer surface of cap614A could be structured to allow for the exit of exhaled CO₂. The outersurface could include a porous surface, or one with a plurality ofholes, as described in U.S. Pat. No. 6,581,594, incorporated herein byreference in its entirety. The outer surface could also include a meshmaterial, to help vent CO₂ in a relatively noise-free manner. FIG. 35shows a partial exploded view of cap 614A. Because seal rings 614 onboth sides of nozzle assembly are identical, the cap 614A and elbow 612can be removed and swapped, depending on whether the patient opts tohave the elbow 612 routed over the left or right side. This can be donewhile the mask assembly is in use on the patient. Also, the elbow 612can be removed to allow for patient mobility.

FIGS. 36-41 illustrate a plug 20 according to yet another embodiment ofthe present invention. Plug 20 is intended to cooperate with a seal,such as seal 614 shown in FIG. 35. Plug 20 includes a first end 22including an enlarged head portion and a second end 24. Adjacent firstend 22 is a enlarged cylindrical portion 26 which forms a shoulder 28with respect to a central portion of tube 20 between first and secondends 22 and 24. Second end 24 includes a slightly enlarged, ring-shapedportion 30. Plug 20 includes one and preferably a pair of key-shapedapertures 32. Plug 20 may be made of polypropylene, e.g., Borealis™, orpolyester. The shape of aperture 32 allows for improved retention andremoval forces, when the plug 20 is in place and when it is removed. SeeFIGS. 36-40. The plug 20 is shown in the assembled position in FIG. 17.

FIG. 41 illustrates a partial cross-sectional view of plug 20 inposition with respect to nozzle assembly 604. As shown, enlarged portion30 is inserted into first connector portion 618. During the insertionprocess, second end 24 is slightly compressed in the radial sense (viaapertures 32) until enlarged portion 30 overcomes the inner edge 623 offirst connector portion 618. Upon reaching the inner edge 623, enlargedportion 30 springs outwardly to thereby fix plug in relation to nozzleassembly 604. In that position, seal portions 626 of seal ring 614 forman airtight seal against the outer surface of cylindrical portion 26. Inaddition, shoulder 28 abuts against end 635 of first connector portion618. As such, the enlarged head of first end 22 extends a distance dthat is spaced slightly away from the end of seal ring 614. For example,distance d is about 1-10 mm or more, but preferably about 3-5 mm.Therefore, the patient or physician can easily grasp enlarged headportion of first end 22 to thereby remove plug 20, for example, in theevent that plug 20 and swivel elbow 612 are to be swapped in accordancewith the preference of the clinician or patient. The enlarged head mayhave a concave outer surface, as seen in FIG. 41.

FIG. 42 illustrates a plug 40 in accordance with yet another embodimentof the present invention. In FIG. 42, plug 40 is intended to be insertedinto one side of nozzle assembly 604, as described above in relation,for example, to the embodiment of FIGS. 36-41. Plug 40 includes a firstend 42 and a second end 44. First end 42 is intended to be insertedwithin nozzle assembly 604. Second end 44 is intended to be providedwith a vent 46 which allows for the passage of exhaled gas. In thisembodiment, vent 46 may be made of a sintered material. Preferably, thesintered material is hydrophobic and allows for the exit of exhaled gasin a relatively noise free manner. In a preferred embodiment, the ventdoes not overly extend away from the nozzle assembly 604, i.e., it has alow lateral profile. Accordingly, the vent 46 can be sized so as to fitwithin seal ring 614 and/or first connector portion of frame 616.

FIGS. 43 and 44 illustrate a cushion 50 according to still anotherembodiment according to the present invention. Cushion 50 includes oneand preferably a plurality of vents 52 to allow passage of exhaled gasfrom the inside of a plenum chamber formed by the cushion 50. In thisexample, the cushion 50 includes six vents 52. FIG. 44 is across-sectional view along section 44-44 of FIG. 43. Each vent 52includes a first end 56 oriented towards atmosphere and a second end 58oriented towards the interior of the plenum chamber. A central portion60 is provided between first and second ends 56, 58. In a preferredform, the central portion 60 includes a substantially conical section,although other cross-sectional areas and shapes are possible. The vent52 has a length which is about 4-8 mm or more, and preferably about 6mm. This increased length as compared to Prior Art FIG. 45B creates amore laminar flow. In addition, the conical shape of central portion 60allows for easier tooling and removing the silicone part from the tool.The conical profile also appears to create less turbulence upon exitingof the exhaled gas.

First end 56 preferably includes a counter bore 62. In this example, thecounter bore has a depth in the range of 0.4 to 0.6 mm or more, and ispreferably about 0.5 mm. The diameter is between 2.5 and 5 mm andpreferably between 3 and 4 mm. The counter bore 62 has an inside radiusof curvature of about 0.1 to 0.2 mm or more, and is preferably about0.15 mm. As such, it may be possible to reduce or eliminate the flashpoint from the air path thus preventing significant noise creation. Withsilicone molding, flash may occur at sharp edges. Therefore, the radiushelps to prevent flash. However, a radius that is too large may lead toundesirable noise. Counter bore 62 may be provided to facilitatemanufacturing, e.g., in the compression molding process.

A portion 64 is provided adjacent counter bore 62. Portion 64 shouldpreferably have a cylindrical cross-sectional shape, i.e., asubstantially straight profile, and forms a transition between theconical central portion 60 and counter bore 62. Portion 64 as formedshould have a length of about 0.4 to 0.8 mm or more, and preferably isabout 0.6 mm. As such, the hole diameter size for flow can be easilycontrolled. The minimum hole diameter, e.g., may range from about 1-3mm, but is preferably about 1.65-1.85 mm, and preferably about 1.75 mm.The diameter at the interior of the conical section may be larger, e.g.,in the range of about 3-4 mm or more, and preferably about 3.0-3.6 mm,or about 3.3 mm.

FIGS. 45A and 45C-45H illustrate additional schematic alternatives forthe size and shape of the vent 52. In these drawings, a partialrectangular sample portion is shown from several views. In order fromleft to right, the views of the sample portion include: a cross sectionthrough each vent with exemplary dimensions; a view from the atmosphereside; a side view showing the relative thicknesses of the main body ofthe patient interface; a view from the interior of the patientinterface; and a cross-sectional view without dimensions. It should benoted that these exemplary vents could also be provided in a ventinsert, an air delivery tube, a tube inlet, e.g., a swivel elbow, and/ora mask frame made of more rigid material, such as polycarbonate. Assuch, these vent profiles are not limited to use with silicone materialor on the patient interface per se. Moreover, the number of holes andthe various features of each profile can be combined in any number ofways, each of which are within the scope of this disclosure.

The dimensions shown on FIGS. 45A and 45C-45H are exemplary, and may bechanged in accordance with the applicable noise requirements, the numberof vents (six in this example), and/or the flow requirements, etc. Forexample, the minimum diameter ranges from about 1.0 mm or less to 3 mmor more, with preferred examples being shown in FIGS. 45A and 45C-45H.FIG. 45B represents a vent used in the prior art. The embodiment shownin FIG. 45G is similar to that shown in FIG. 44. FIG. 45G illustratesthe vent 52 shown in FIG. 44. FIG. 45E is similar to FIG. 45G, but doesnot include a substantially cylindrical portion, like portion 64 shownin FIG. 44. Portion 64 can vary in length, as can be seen from thecomparison of FIGS. 45C and 45F.

FIGS. 46-48 illustrate baffles 70 in accordance with another embodimentof the present invention. Baffles 70 are shown in conjunction with theframe 616 of nozzle assembly. Frame 616 is similar to the framesdescribed above. The baffle 70 shown in perspective in FIG. 46 is alsoshown in elevation view in FIG. 48. This baffle includes a pair of arms72 which are longer than the arms 74 shown in FIG. 47. Baffles 70 helpto reduce cyclic noise by creating additional turbulence within the maskand also at least partially separate vent exit from the air inlet whichmay be beneficial for both noise and minimization of CO₂. Baffles 70include a base plate 76 which supports arms 72, 74. Base plate 76 isconnected or otherwise provided to an inside portion of frame 616. Forexample, as shown in FIG. 46, base plate 76 may include an aperture 78which is intended to receive a complimentary shaped protrusion providedas part of frame 616.

FIGS. 49-51 illustrate an elbow 612 according to yet another embodiment.As compared to elbow 612 shown in FIG. 114, elbow 612 in FIGS. 49-51includes one and preferably a pair of key-shaped apertures 613. Theelbow may be made of polypropylene, e.g., “Borealis,” or polyester. Theshape of the apertures allows for improved retention and removal forces,when the elbow is in place and when it is removed.

FIGS. 52-54 illustrate a frame 616 according to another embodiment. Theframe 616 is substantially similar to the frames described above. Incontrast, the frame 616 includes a vent 625 structured to allow for theexit of exhaled gas. The vent 625 may be instead of or supplemental tothe vent provided on the cushion and/or plug.

For example, the frame 616 includes a main body 627 and a side framemember 629 provided on each lateral side of the main body 627. Each sideframe member 629 includes an integrally formed first connector portion618. As illustrated, the main body 627 includes a vent 625 in the formof one and preferably a plurality of vent apertures 690 to allow passageof exhaled gas. Each vent aperture 690 may be formed by a separate tubethat extends through the main body 627, as best shown in FIG. 54.Preferably, the vent apertures 690 are integrally formed in one piecewithin the main body 627, e.g., as through holes. However, the ventapertures 690 may be formed in the main body 627 in any other suitablemanner.

In the illustrated embodiment, the frame 616 includes five ventapertures 690. However, the frame 616 may have any suitable number ventapertures 690. Also, the vent apertures 690 may be spaced apart from oneanother in any suitable manner, e.g., equally or unequally spaced apartfrom one another.

FIG. 54 shows a possible profile of the vent apertures 690. Asillustrated, each vent aperture 690 includes a first end 656 orientedtowards atmosphere and a second end 658 oriented towards the interior ofthe plenum chamber formed by the cushion. A central portion 660 isprovided between the first and second ends 656, 658. In the illustratedembodiment, the central portion 660 includes a substantially conicalshape having a varying diameter that is larger towards the second end658. This configuration helps to create less turbulence upon exiting ofexhaled gas. However, the conical shape may have any suitable size andvarying diameter. Moreover, the central portion 660 may have any othersuitable shape. For example, the vent apertures 690 may have sizes andshapes such as those vents disclosed in FIGS. 45A and 45C-45H. Further,the configuration, dimension, and number of vent apertures 690 may bemodified in any suitable manner in order to provide, e.g., desired noiserequirements and/or flow requirements.

Similar to the frames described above, the frame 616 is constructed of asubstantially rigid material, e.g., plastic or polycarbonate. The rigidconstruction enables the frame 616 to be produced with a consistent ventshape and dimension (without rough edges, flash, or damage to the ventapertures), which results in providing a frame 616 with consistently lowvent noise and a consistent flow rate.

Additionally, the vent apertures 690 are provided along the entirelength of the main body 627 of the frame 616. This arrangement increasesthe length of the vent path, which reduces the turbulence in the ventapertures 690 and creates a more laminar flow from the vent apertures690. Thus, less noise is generated from the vent apertures 690.

However, the vent 625 in the main body 627 of the frame 616 may have anyother suitable structure to allow for the exit of exhaled gas. Forexample, the main body 627 may include a porous surface, a meshmaterial, etc.

Further, the nozzle assembly and/or its associated cushion could bereplaced with a nasal mask and/or nasal cushion 501. See, e.g., FIGS.55, 56, and 57. FIGS. 55 and 56 show arrangements in which the frame 516includes opposite apertures or first connector portions 518 (e.g.,tubular extensions), each of which is provided with a seal ring asdescribed above. A seal ring is adapted to include a separate orintegral plug 500 to close one aperture or first connector portion ofthe frame, while another seal ring is adapted to engage with the otherframe aperture/first connector portion, and to receive the swivel elbow506. Of course, the positions of the elbow 506 and plug 500 may beinterchanged, depending on patient preference. In FIG. 55, the nasalmask is similar to ResMed's VISTA mask with the elbow 506 provided tothe side of the mask frame 516. Further details and embodiments of theframe in FIG. 55 are disclosed in U.S. patent application Ser. No.10/391,440, filed Mar. 19, 2003, the entirety of which is herebyincorporated herein by reference. The nasal cushion 501 in FIG. 55 isstructured to sealingly engage lower nasal bridge, cheek, and lipregions of the patient in use. In FIG. 56, the nasal mask includes anasal cushion 501, having a gusset portion, structured to sealinglyengage upper nasal bridge, cheek, and lip regions of the patient in use,such as the patient interface commercially sold under the name ofActiva® by ResMed Ltd. Further details and embodiments of the cushion inFIG. 56 are disclosed in U.S. patent application Ser. No. 10/655,622,filed Sep. 5, 2003, the entirety of which is hereby incorporated hereinby reference. In FIG. 57, the elbow 506 is provided to the front of themask frame 516, like ResMed's VISTA mask, while both apertures/firstconnector portions are provided with plugged seal rings. Further detailsand embodiments of the elbow in FIG. 57 are disclosed in U.S. patentapplication Ser. No. 10/390,826, filed Mar. 19, 2003, the entirety ofwhich is hereby incorporated herein by reference. Of course, in eachembodiment, frame, elbow, and/or seal ring(s) may be provided withappropriate vents to exhaust exhaled gas from the breathing chamber.

FIG. 58 illustrates another arrangement in which the above-describednozzle assembly 604 is utilized with headgear 702 according to anotherembodiment of the present invention. As illustrated, the headgear 702has a spectacles-type construction that provides side portions 703 thatwrap around the patient's ears and an intermediate portion 705 thatrests on the patient's nose. Yokes 708 extend from the intermediateportion 705 and include yoke rings 710 adapted to engage with respectiveconnector portions provided on the nozzle assembly 604. One end of thecushion assembly 604 is provided with a plug 622 and the other end isprovided with a swivel elbow 612. The positions of the swivel elbow 612and the plug 622 may be interchanged, depending on patient preference.The headgear 702 provide a lightweight and low profile arrangement thatmay be used as an alternative to headgear 602 to support the nozzleassembly 604 on the patient's head.

While the invention has been described in connection with what arepresently considered to be the most practical and preferred embodiments,it is to be understood that the invention is not to be limited to thedisclosed embodiments, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the invention. In addition, while the invention has particularapplication to patients who suffer from OSA, it is to be appreciatedthat patients who suffer from other illnesses (e.g., congestive heartfailure, diabetes, morbid obesity, stroke, barriatric surgery, etc.) canderive benefit from the above teachings. Moreover, the above teachingshave applicability for use with patients and non-patients alike.

What is claimed is:
 1. A patient interface for sealed delivery of a flowof breathable gas at a continuously positive pressure with respect toambient air pressure to an entrance to a patient's airways including atleast entrance of a patient's nares, while the patient is sleeping, toameliorate sleep disordered breathing, the patient interface comprising:a patient contacting portion forming a plenum chamber and adapted tosealingly engage with a patient; and a vent assembly configured to ventgas from the plenum chamber, the vent assembly including at least onevent having a first end configured to face atmosphere, a second endopposite the first end and configured to face the plenum chamber, and acentral portion provided between the first and second ends including asubstantially cylindrical cross-ectional shape, wherein the first endincludes a counter bore, the counter bore of the first end comprising afirst diameter, wherein the second end includes a counter bore, thecounter bore of the second end comprising a second diameter, wherein thefirst diameter is substantially similar to the second diameter, andwherein the first and second diameters are relatively larger than adiameter of the central portion.
 2. The patient interface according toclaim 1, wherein the counter bore of the first end and the counter boreof the second end each includes a depth similar to a depth of thecentral portion.
 3. The patient interface according to claim 1, whereinthe second end is structured to reduce or eliminate noise creating flashfrom an air path.
 4. The patient interface according to claim 1, whereinthe counter bore of the first end includes a depth similar to a depth ofthe counter bore of the second end.
 5. The patient interface accordingto claim 1, wherein the patient contacting portion is a nozzle assembly.6. The patient interface according to claim 1, wherein the patientcontacting portion is a nasal cushion.
 7. The patient interfaceaccording to claim 1, wherein the vent assembly includes at least onevent provided on the patient contacting portion.
 8. The patientinterface according to claim 1, wherein the vent assembly includes atleast one vent provided on a frame that at least in part supports thepatient contacting portion.
 9. The patient interface according to claim1, wherein the vent assembly includes a plurality of vents equallyspaced apart from one another.
 10. The patient interface according toclaim 1, wherein the vent assembly includes a plurality of ventsunequally spaced apart from one another.